<template>

  <el-menu
    :default-active="activeMenu"
    style="background-color: transparent;"
    class="elmenu"
    mode="horizontal"
    @select="handleSelect"
    :active-text-color="settings.sideTheme === 'theme-dark' ? variables.menuColorActive : variables.menuLightColorActive"
    :text-color="settings.sideTheme === 'theme-dark' ? variables.menuColor : variables.menuLightColor"
    :background-color="settings.sideTheme === 'theme-dark' ? variables.menuBackgroundNav : variables.menuLightBackgroundNav"
  >

    <template v-for="(item, index) in topMenus">
      <el-menu-item
        :style="{'--theme': theme}"
        :index="item.path"
        :key="index"
        v-if="index < visibleNumber"
      >
        <template v-if="item.meta.icon">
          <!-- <svg-icon :icon-class="item.meta.icon" /> -->
        </template>
        <span style="font-weight: 700;">{{ item.meta.title }}</span>
      </el-menu-item>
    </template>

    <!-- 顶部菜单超出数量折叠 -->
    <template>
      <el-submenu
        :style="{'--theme': theme}"
        index="more"
        style="height: 100%;"
        v-if="topMenus.length > visibleNumber"
      >
        <span
          slot="title"
          class="titleMore"
          :style="{color: settings.sideTheme === 'theme-dark' ? variables.menuColor : variables.menuLightColor}"
        >更多菜单</span>
        <template v-for="(item, index) in topMenus">
          <el-menu-item
            :index="item.path"
            :key="index"
            v-if="index >= visibleNumber"
          >
            <svg-icon
              style="color:#496dff; "
              :icon-class="item.meta.icon"
            />
            <span style="padding-left: 10px;">{{ item.meta.title }}</span>
          </el-menu-item>
        </template>
      </el-submenu>
    </template>
  </el-menu>
</template>

<script>
import { mapState } from "vuex";
import { constantRoutes } from "@/router";
import variables from "@/assets/styles/variables.scss";

export default {
  data() {
    return {
      // 顶部栏初始数
      visibleNumber: 7,
      // 是否为首次加载
      isFrist: false,
      // 当前激活菜单的 index
      currentIndex: undefined,
    };
  },
  computed: {
    ...mapState(["settings"]),
    theme() {
      return this.$store.state.settings.theme;
    },
    variables() {
      return variables;
    },
    // 顶部显示菜单
    topMenus() {
      const topMenus = [];
      this.routers.map((menu) => {
        if (menu.hidden !== true) {
          // 兼容顶部栏一级菜单内部跳转
          if (menu.path === "/") {
            topMenus.push(menu.children[0]);
          } else {
            topMenus.push(menu);
          }
        }
      });
      return topMenus;
    },
    // 所有的路由信息
    routers() {
      return this.$store.state.permission.topbarRouters;
    },
    // 设置子路由
    childrenMenus() {
      var childrenMenus = [];
      this.routers.map((router) => {
        for (var item in router.children) {
          if (router.children[item].parentPath === undefined) {
            if (router.path === "/") {
              router.children[item].path =
                "/redirect/" + router.children[item].path;
            }
            router.children[item].parentPath = router.path;
          }
          childrenMenus.push(router.children[item]);
        }
      });
      return constantRoutes.concat(childrenMenus);
    },
    // 默认激活的菜单
    activeMenu() {
      const path = this.$route.path;
      let activePath = this.defaultRouter();
      if (path.lastIndexOf("/") > 0) {
        const tmpPath = path.substring(1, path.length);
        activePath = "/" + tmpPath.substring(0, tmpPath.indexOf("/"));
      } else if (path == "/index" || path == "") {
        if (!this.isFrist) {
          this.isFrist = true;
        } else {
          activePath = "index";
        }
      }
      var routes = this.activeRoutes(activePath);
      if (routes.length === 0) {
        activePath = this.currentIndex || this.defaultRouter();
        this.activeRoutes(activePath);
      }
      return activePath;
    },
  },
  beforeMount() {
    window.addEventListener("resize", this.setVisibleNumber);
  },
  beforeDestroy() {
    window.removeEventListener("resize", this.setVisibleNumber);
  },
  mounted() {
    this.setVisibleNumber();
  },
  methods: {
    // 根据宽度计算设置显示栏数
    setVisibleNumber() {
      const width = document.body.getBoundingClientRect().width / 3;
      this.visibleNumber = parseInt(width / 85);
    },
    // 默认激活的路由
    defaultRouter() {
      let router;
      Object.keys(this.routers).some((key) => {
        if (!this.routers[key].hidden) {
          router = this.routers[key].path;
          return true;
        }
      });
      return router;
    },
    // 菜单选择事件
    handleSelect(key, keyPath) {
      this.currentIndex = key;
      if (this.ishttp(key)) {
        // http(s):// 路径新窗口打开
        window.open(key, "_blank");
      } else if (key.indexOf("/redirect") !== -1) {
        // /redirect 路径内部打开
        this.$router.push({ path: key.replace("/redirect", "") });
      } else {
        // 显示左侧联动菜单
        this.activeRoutes(key);
      }
    },
    // 当前激活的路由
    activeRoutes(key) {
      var routes = [];
      if (this.childrenMenus && this.childrenMenus.length > 0) {
        this.childrenMenus.map((item) => {
          if (key == item.parentPath || (key == "index" && item.path == "")) {
            routes.push(item);
          }
        });
      }
      if (routes.length > 0) {
        this.$store.commit("SET_SIDEBAR_ROUTERS", routes);
      }
      return routes;
    },
    ishttp(url) {
      return url.indexOf("http://") !== -1 || url.indexOf("https://") !== -1;
    },
  },
};
</script>

<style lang="scss">
.topmenu-container.el-menu--horizontal > .el-menu-item {
  line-height: 62px !important;
  -webkit-transition: border-color 0s;
  background-color: transparent !important;
  transition: border-color 0s;
  padding: 0 !important;
  border-bottom: 0;
  height: 75% !important;
  margin: 0 30px !important;
  transition: 0.3s !important;
  &::before {
    content: "";
    position: absolute;
    bottom: 0;
    width: 30px;
    height: 3px;
    border-radius: 5px;
    transition: 0.3s;
  }
  &:hover {
    opacity: 0.8;
    &::before {
      background-color: #195eff6e !important;
    }
  }
}

.topmenu-container.el-menu--horizontal > .el-menu-item.is-active,
.el-menu--horizontal > .el-submenu.is-active .el-submenu__title {
  position: relative;
  top: 0;
  left: 0;
  border-bottom: 0px !important;
  height: 100%;
  &::before {
    content: "";
    position: absolute;
    bottom: 0%;
    width: 30px;
    height: 3px;
    background-color: #195fff;
    border-radius: 5px;
    transition: 0.3s;
  }
}

.el-menu.el-menu--horizontal {
  border-bottom: 0 !important;
}
.el-menu--horizontal > .el-menu-item:not(.is-disabled):hover {
  background-color: rgba($color: #ffffff, $alpha: 0.1);
  border-radius: 3px;
}
/* submenu item */
.topmenu-container.el-menu--horizontal > .el-submenu .el-submenu__title {
  float: left;
  height: 49px !important;
  font-size: 15px !important;
  padding: 0 5px !important;
  margin: 0 10px !important;
}
.elmenu {
  background-color: rgba($color: #000000, $alpha: 0);
}
</style>

<style scoped >
.titleMore {
  display: block;
  font-size: 14px;
  font-weight: bold;
  height: 100% !important;
  line-height: 65px !important;
}
.el-menu--horizontal /deep/ .el-submenu .el-submenu__title:hover {
  background-color: transparent !important;
}
</style>
